Lower-GWP Alternatives in Stationary Air Conditioning: A Compilation of Case Studies

Stationary air conditioning systems are used to provide cooling for indoor occupants for their thermal comfort at a suitable indoor air quality. Within the cooling sector the stationary air conditioning sub-sector represents the largest and most rapidly growing area of HFC use. It is associated with significant indirect emissions of CO2 due to electricity consumption, particularly in developing countries.

In order to encourage industry and government policymakers to implement the phase-down of HFCs in stationary air conditioning through the adoption of lower-GWP energy efficient refrigerants, the CCAC has developed this booklet of ten case studies from around the globe, which represents various countries, climates and alternative technologies. This booklet can also serve as a reference guide for end-user and system purchasers on factors to consider when transitioning to lower-GWP air conditioning. While the case studies mainly discuss experiences relating to transitioning from HFCs to lower-GWP refrigerants, the information provided is also relevant for transitioning directly from HCFCs to such refrigerants.

With the aim of providing information on the successful adoption of a range of refrigerants, technologies and geographic locations, ten examples were selected from the case studies submitted. The selected case studies consider the energy efficiency benefits of the alternative system, as well as the cost, safety, availability and environmental impacts. Robust technical information was collected in the chosen case studies based on data provided by the source.

The case studies in this booklet discuss several applications in the stationary air conditioning sector. The applications include chillers of natural refrigerants and hydrofluoroolefins (HFOs) as well as split-units which use hydrocarbons (HCs) as the refrigerant. The technologies presented in these case studies are only some examples of the many available options for zero and lower GWP substances. The examples take into account design criteria such as system performance, environmental impact and cost. All these refrigerants still have many challenges that should be considered in the design, for example their flammability, toxicity, lower efficiency in some cases, and cost. Balancing these challenges using a consistent and comprehensive methodology across all refrigerants and system types is essential in assessing alternatives. To ensure that refrigerant emissions are reduced during the installation, operation, maintenance, decommissioning and disposal, two key parameters need to be provided. These parameters are: provide a good design for the cooling system and: train technical staff on good engineering practices to ensure the most adequate handling of the equipment during all phases of the air conditioning unit’s lifecycle. 

Future Needs for Cooling and Heating
It is important to transition to lower-GWP refrigerants today as the future need for cooling and heating is expected to significantly increase over the next decades . It is also crucial that the stationary air conditioning sector further improves the unit component designs; otherwise the direct and indirect emissions will proportionally increase with the cooling and heating demand.